Edward Burger and Colin Adams aren't yet as well known as such famous comedy teams as Laurel and Hardy... but they are not only performers but also math professors at Williams College in Williamstown, Mass. They bring antic energy, slapstick humor, and pointed satire to their presentations of mathematics. Their topic is really topology, and much of the talk concerns what kinds of shapes can be cast using a two-piece mold. Their quick "paper napkin" sketches look suspiciously like diagrams on overhead transparencies. The discussion also takes place on a stage, and the dialog is from a two-act play called "Casting About: About Casting."